Fixed IsValidPath usages

(cherry picked from commit 033936dce7e13c8ab2e38407782dc9cdd949460e)

Closes #3470

src/NzbDrone.Core.Test/HealthCheck/Checks/RemotePathMappingCheckFixture.cs

@@ -83,7 +83,7 @@ namespace NzbDrone.Core.Test.HealthCheck.Checks
                 .Setup(x => x.FolderExists(It.IsAny<string>()))
                 .Returns((string path) =>
                 {
-                    Ensure.That(path, () => path).IsValidPath();
+                    Ensure.That(path, () => path).IsValidPath(PathValidationType.CurrentOs);
                     return false;
                 });
 
@@ -91,7 +91,7 @@ namespace NzbDrone.Core.Test.HealthCheck.Checks
                 .Setup(x => x.FileExists(It.IsAny<string>()))
                 .Returns((string path) =>
                 {
-                    Ensure.That(path, () => path).IsValidPath();
+                    Ensure.That(path, () => path).IsValidPath(PathValidationType.CurrentOs);
                     return false;
                 });
         }

src/NzbDrone.Core/HealthCheck/Checks/RemotePathMappingCheck.cs

@@ -150,7 +150,7 @@ namespace NzbDrone.Core.HealthCheck.Checks
                         return new HealthCheck(GetType(), HealthCheckResult.Error, $"Lidarr failed to import a track.  Check your logs for details.");
                     }
 
-                    if (!dlpath.IsPathValid())
+                    if (!dlpath.IsPathValid(PathValidationType.CurrentOs))
                     {
                         if (!status.IsLocalhost)
                         {